Fluorescent circuit tester



y 24, 1956 J. L. MEYER FLUORESCENT CIRCUIT TESTER Filed Nov. 21, 195] III/III Im- 11/ In 00????" tfanz. Jfeyer @QA. M

United States Patent FLUORESCENT CIRCUIT TESTER John L. Meyer, Elgin, 11]., assignor to Ideal Industries, Inc., Sycamore, 111., a corporation of Delaware Application November 21, 1951, Serial No. 257,515

1 Claim. (Cl. 324-23) contains the indicator or tester, and the adapter, in a single overall unit.

Another object is to provide such a testing device with a minimum number of parts.

Another object is to provide a tester which will test all makes of fluorescent lamps regardless of starter location.

Other objects will appear from time to time throughout the specification and claim.

The invention is illustrated more or less diagrammatically in the accompanying drawings wherein:

Figure l is a side elevation of the device.

Figure 2 is a vertical section on an enlarged scale, at line 22 of Figure 1.

Figure 3 is a horizontal section of the indicating unit taken along line 33 of Figure 2.

Figure 4 is a plan view of one half of the base portion of the indicating unit.

Figure 5 is a side elevation of one of the halves forming the base portion of the indicating unit and looking into such portion.

Figure 6 is a detail showing in side elevation the lower extremity of one of the base portion halves.

Figure 7 is a side elevation of the tester button.

Figure 8 is a vertical section of the terminal unit showing a capacitator in operative position.

1 indicates generally an indicating unit which has a translucent and preferably transparent cap 2 and a base portion 3. For ease of manufacture and repair I prefer to have the base portion 3 of the indicating unit made up of two parts or halves 4 and 5, as shown in Figure 2, these parts fitting together on each side along a seam 6 and each part having along its vertical edge a depression 7 and pin 8, as shown in Figures 2, 5 and 6, such depression and pin of each of the halves 4 and 5 interfitting as shown in Figure 4 with the opposing pin and depression in the other half. The cap 2 then preferably fits over the abutting and interfitting parts 4 and 5 at the neck 9 of the base portion 3, as shown in Figure 2. Preferably this fit should be tight, and glue or cement may be used to effect security.

The base portion 3 is preferably greater in diameter than is the cap portion 2. Such a shape in the overall indicating unit results in the provision of a convenient finger grasp for the user, whereby two fingers, as the index and second finger, may fit around opposite sides of the indicating unit where the base portion decreases in size, and the thumb may be easily placed against the button 26.

In the indicator 1 is a gas-filled bulb 10 which may be a standard part, in which case its threaded shell 2,756,384 Patented July 24, 1956 portion 28 conveniently serves as an electrical contact point. The bulb 10 may be conveniently held in place by an inwardly extending dome or cap 29 and by a wire spring 24. Within the bulb 10, as shown in Figures 1 and 2, are posts or wires 11 and 12 leading respectively to electrodes 13 and 14. A non-conducting reinforcing piece 15 may be used to render the wires 11 and 12 secure. The wires 11 and 12 are respectively joined, in a conventional manner, to a central contact point 17 depending from the shell portion 28. There is preferably provided, above the contact point 17, an area 16 of insulation. The contact point 17 is joined, by solder or any other suitable means, to a starter wire 18, which is provided with insulation 19. The wire 18 thence passes to the outside of the base portion 3 through an outlet opening 20 and extends through an inlet opening 21 in a terminal unit 22 to an adapter contact 23.

In contact with and leading from the bulb shell 28 is a wire spring 24, which constitutes an electrical conductor between the bulb shell 28 and an intermediate conductnig means 25. The intermediate conducting means 25 is preferably in the form of a sleeve as shown, and is mounted, and most conveniently centered, on the tester button 26, as shown in Figure 2, a detail of the button 26 being shown in Figure 7. The button 26 may, in order to facilitate the centering thereon of the intermediate conducting sleeve 25, be characterized by bosses or guiding fingers 27. The spring 24 is thus at its upper end in contact with the bulb shell 28 and at its lower end with the sleeve 25. It at all times exerts between the bulb shell 28 and the sleeve 25 a pressure which is effective to separate the sleeve and the Wire 18 until pressure on the button 26 is greater than the resistance of the spring.

Leading from an upward extension 30 of the intermediate conducting means 25 is another starter wire 31, corresponding to starter wire 18 and provided with insulation 32. The wire 31 passes to the outside of base portion 3 through an outlet opening 37, and extends through the inlet opening 21 in terminal unit 22 to adapter contact point 33.

A grommet 38 may be positioned about the terminal unit inlet opening 21 to protect the wires 19 and 31.

A capacitator or condenser 34, connected to contact points 23 and 33 by wires 35 and 36 may be provided, as shown in Figure 8, in high-voltage testers to protect the contact points from discharge when electrical contact is broken.

Having the wires 18 and 31 secured at one end of each within the indicating unit 1 and at the other end to the terminal 22 results in a tester comprising a single device formed of two main parts joined by a flexible connection. In the use of this tester it is, therefore, not necessary to connect two separate pieces to provide an operating mechanism suitable for use with sockets of every type. The structure, as shown, accomplishes that purpose.

The use and operation of my invention are as follows:

When a fluorescent tube fails to light normally and it is desired to determine the defect or defects causing the malfunction, the starter of the fluorescent fixture should be removed and the adapter contacts 23 and 33 inserted in the starter socket with the fixture tube in place. The switch from the main power source will, of course, be on. If the circuit in the fixture being tested is operative, the indicating unit 1 will light with the button 26 in the undepressed or outward position shown in Figure 2. Current will pass from adapter contact 23 through wire 18 to bulb contact point 17, thence through the wire 12 to the electrode 14; will are from electrode 14 to electrode 13, pass down wire 11 to threaded shell 28 and from shell 28 to the wire spring 24. The wire spring 24 will carry the current on to the intermediate conducting means 25,

. 3 and wire 31 will conduct it to adapter contact 33, completing the circuit.

This condition-that is, a condition wherein the indicating unit lights with the button 26 in the undepressed or outward position and with the original fixture tube in place-indicates that the fixture circuit is operative. Failure of the indicating unit to light indicates faulty ballast, wiring or power source. v

After making his check on the fixture circuit, the operator should depress the button 26 until the ends of the fixture tube glow, then release the button. The testcr then acts as a starter, the extension 30 of intermediate conducting means 25 coming in contact with wire 18 and, otfering the line of least resistance to the current flowing through the wire 18, passes the current directly to wire 31, short circuiting wires 11 and 12 and electrodes 13 and 14. If the fixture tube lights, it is known that the original starter was defective and should be replaced.

If, however, the tube under these conditions fails to' light, a new tube should be installed and the same test made. If the new fixture tube lights, it is knownthat the former tube was defective.

The original starter should'then be re-installed. If the original starter fails to lightthe new tube, it is known that both the original tube and the original starter were defective and a new starter must also be installed.

Although I have shown an operative form of my invention, it will be recognized that many changes in the form, shape and arrangement of parts can be made without departing from the spirit of the invention, and my show ing is, therefore, to be' taken as, in a sense, diagrammatic.

I claim:

In a lighting assembly, a housing with a closed transparent portion mounted on a base, a lamp therein with a bulb in the transparent portion of the housing and terminals extending into the base, a manually operable button slidably mounted in the base opposed to the terminals on the lamp and extending through an opening in thebottom of the base, an abutment in the base to limit the outermost position of the button, a seat in the top of the transparent portion receiving the top of the bulb, a coil metallic spring between one terminal of the lamp and the button, and two electric wires leading through the base, one wire being connected to the other terminal and the other wire being connected to the end of the coil spring against the button, the spring being under compression in its normal state so that it biases the button to its outermost position and the bulb against its seat in the top of the transparent portion, manual actuation ofthe button being effective to compress the spring to establish contact between the two electric wires to'shortout the lamp.

' References Cited in the file of this patent UNITED STATES PATENTS 

